1. Field of the Invention
The present invention relates to a device for removing deposited animal excrement from a surface.
2. Description of the Prior Art
Concern over the health risks and general unpleasantness occasioned by canine excrement in particular has led to the development of a number of devices for the removal of canine excrement form the surfaces of public places. Examples of such devices are shown in patent specifications GB 2,225,492; 2,236,271; 2,227,645; EPO 561 093 and WO 95/17810.
Specification GB 2,255,492 discloses a device in the form of a hollow walking stick in which there is a spring-loaded piston to which are attached a number of claws. The piston rod projects from the top of the walking stick and terminates in a handle. In use, the handle is pushed downwards to cause the claws to project from the bottom of the walking stick and to compress a spring and the claws are placed around a deposit of excrement to be removed. When the spring is released by means of a trigger within the handle, the piston is withdrawn into the body of the walking stick causing the claws to close around the excrement and draw it into the body of the walking stick assisted by the suction created by a piston seal. The device is cumbersome and not aesthetically pleasing.
Specification GB 2,236,291 discloses a device in which an inner tubular member terminates in an array of spring fingers which are biased outwardly but held in a closed configuration by an outer tubular member which can be moved upwardly to release the fingers to an open configuration, enabling them to be placed around a deposit of excrement and then downwardly to close around the excrement. Although the device may achieve its purpose, the components have to be moved manually.
Specification GB 2,227,645 A discloses a device in which a scoop has a lower blade and a movable upper blade forming a pair of tongs. The tongs are used in conjunction with a plastics bag which is placed around the tongs in such a way that there is a re-entrant portion of the plastics bag between the tongs. In use, the lower blade of the tongs is slid under a deposit of excrement until it is within the bag whereupon the tongs are closed to hold the excrement within the bag while it is slid off the tongs and enclosed within the bag.
Again, the device may be effective but it is cumbersome.
Specification EPO 561093 discloses a device which is very similar to that disclosed in GB 2,225,492 and similar remarks apply.
Specifications WO 95/17810 discloses a device which consists of a scoop mounted on a handle. The scoop is closed by a cover which can be moved forward by a linkage attached to the handle so that the device can be placed with the scoop on one side of a deposit of excrement and the cover on the other and the linkage operated to move the cover towards the scoop so sweeping the excrement into the scoop so sweeping the excrement into the scoops. The handle also acts as a reservoir for a liquid bactericide which can be discharged over the area from which the excrement has been removed.
EPO 510 472 A1 discloses an arrangement in which there are two tubular members, one of which can move within the other. Within the inner tube is housed, movably, a gripping member which includes a plurality of outwardly-biased claws. A coil-spring is included which acts to urge the inner of the two tubular members outwards. In use, initially the gripping member is pushed into the inner tubular member and that the inner tubular member is pushed into the outer member, so compressing the coil spring, and retained therein by means of a latch. To operate the device, the gripping member is withdraw from the inner tubular member, a plastics bag is placed over the free ends of the claws, the claws and the plastics bag are placed over excrement it is desired to remove from a surface and the latch is released. The spring urges the inner tubular member over the gripping member so causing the claws of the gripping member to close around the excrement and enclose it within the inner tubular member for later disposal.
A disadvantage of this device is that the gripping member has to be withdrawn manually from the outer member to deploy the gripping member when the gripping member. Also, when the gripping member is placed over the excrement, there is a tendency for the gripping member to move back into the inner tubular member.
Our earlier patent application GB0122664.6 discloses a device which has two tubular members, one of which can move within the other. A coil spring contained within the outer tubular member acts to expel the inner tubular member from the outer tubular member. The coil springs surround an axial core, to the free end of which there are attached three outwardly-biased claws of a length such that when the inner member is extended from the outer member, the claws are contained within the inner member. To use the device, the inner tubular member is pushed into the outer tubby member, so exposing the claws and enabling then to deploy themselves. At the same time the coil spring is compressed and a latch is engaged to retain the inner tubular with the outer tubular member. A plastics bag is then placed over the free ends of the claws and the bag and claws are placed over excrement to be removed from a surface, as in the device of EP 0510 472 A2, the latch is released, the inner tubular member is extended from the outer tubular member, causing the claws to close around the excrement so that it can be lifted from the surface and contained within the extended inner tubular member for later disposal.
This device overcomes the disadvantages of that of EP 0510 472 A2 because the deployment of the claws takes place automatically when the inner tubular member is pushed into the outer tubular member and there is no tendency for the claws to move back into the outer tubular member when they are placed around the excrement.
However, unless the diameter of the outer tubular member is relatively large, the volume of excrement which can be lifted by the device is limited—the same is true of the device of EP 0510 472 A2.
Specification U.S. Pat. No. 4,819,877 and GB 2,236,271 A both disclose devices in which an outer tube is moved over an inner tube both to deploy and enclose fingers which can be placed over animal feces so as to enable it to be removed from a surface.
However, in both cases, the outer tube is cylindrical and has to be moved manually both to deploy and enclose the fingers. Thus, these devices also are restricted in terms of the volume of feces they can remove. Also, the manual movement of the outer tube is a disadvantage, because it can cause the grabs to move in relation to the feces, makes the use of the devices cumbersome, because the use of two hands is necessary to operate the devices, and could cause an element of unpleasantness to sensitive people.
It is an object of the present invention to provide an improved device for removing animal excrement from a surface.